Japan's cabinet has approved new sanctions against Iran, including an assets freeze on figures linked to Tehran's disputed nuclear programme and tighter restrictions on financial transactions.

The government also announced on Friday that it would suspend any new oil and gas investments in Iran, but there are no plans to restrict imports of crude oil from the country, a major energy supplier to resource-poor Japan.

"Our nation has traditionally had a close relationship with Iran," Yoshito Sengoku, a top government spokesman, told reporters.

"From this unique position, we will make persistent calls on the country for the peaceful and diplomatic resolution of this problem."

The move comes a month after Tokyo approved punitive measures in line with a June UN Security Council resolution, which slapped a fourth set of sanctions on Iran over its refusal to halt uranium enrichment work.

Asset freeze

Japan's new sanctions include a freeze on the assets of 88 groups and 24 individuals linked to Iran's country's nuclear programme, which many nations fear masks a drive for atomic weapons, a government document said.

Japan will also bar the individuals on the expanded blacklist from entering the country, it said.

The new package of sanctions also prohibits Japanese financial institutions from dealing in bonds issued by Iran's central bank and equities linked to any activities to develop nuclear arms or other weapons of mass destruction.

The United States, European Union, Canada and Australia have also announced additional sanctions, which have been opposed by Russia and China, now Iran's closest trading partner, with major energy interests in the country.

Last month, Washington urged Tokyo to help raise international pressure on Tehran, despite Japan's usually friendly ties with the country.

In early August, Robert Einhorn, the US state department special adviser for non-proliferation and arms control said in Tokyo: "Japan imports a lot of oil from Iran, but the steps we are asking Japan to take would not interfere in any way with Japan's energy security, its imports of oil from Iran."

Iran maintains that its nuclear programme is peaceful, and not a front for the development of nuclear weapons.